Type-writing machine.



J. c. MoLAUGHLIN.

TYPE WRITING MAOH'INB. APPLIOAIION FILED JULY 3,1908.

924,096. Patented June 8,1909.

UNITED STATES JOHN, (.ltIcLr XUGHLIN, F JEBSEYCITY, NEW JERSEY, ASSIGNOR T0.UNDERWOOD WRITER COMPANY. OF NEW YORK; N. Y., A CORPORATION .01" NEW JERSEY. I

PATENT OFFICE.

TYPE- 'TYPEWRI' 1ING MACHINE.

Specification of Letters Patent.

Patented June 8, 1909.

Application filed July 3, 1908. Serial No. 441,799.-

'1 '0 all whom it may concern:

Be it known that I. Join: (J. h/iC-LA oouuu, a citizen of the UnitedStates, residing in Jersey City, in the State of New Jersey, have invented certain new and useful Improvements in Type-Writ- -ing Machines, of which the following is a specification. This invention relates to the linespacing chines.

It often happens, when a nervous operator gives an unusually uick stroke to the lever which operates the p aten-driving pawl, that the lat-en over-throws. This is due rincipalii' to the weight of the platen, the usual spring detent being insufficient to arrest the platen at the proper oint wlmn' the platen has received unusual y great impetus from the jerky stroke of the spacing lever. platen is sometimes overthrown only a portion ofa line-space, and during the writing of a line it sometimes happens that the spring detent, acting upon the teeth of the ratchet wheel, gradually forces the platen back to its proper position; such gradual back rotation of the laten having the effect to cause the written ietters to form a curved or slantmg line instead of a straight line across the page.

The object of the present invention is to provide simple and inexpensive means for overcoming this disadvantage.

in carrying out the invention the usual revoluble platen a double ratchet or liue space wheel with the teeth of one wheel opposed to the teeth of the other, and pivot to a manually-driven men'ihera device having two teeth, one tooth to engage with one portion of the line-space wheel to turn the platen, and the gage the other portion of said wheel, and co- I connect to operating-with. a stop on the platen frame to arrest or lock the platen at the end of the stroke of the manually-driven member.

in the accompanying drawings,[Figure 1 is a perspective view of an Underwood typewriting machine, with my improvements applied thereto, and in platensarresting positions. Fig. 2 is an end elevation, showing in full lines the line-spacing mechanism in normal 'platemarresting or looking position.

In this county of Hudson and,

pawl-and-ratchet mechanism of: writing ma The beginning of other tooth to en position, and in dotted lilies the same in" View the mechanism is set for triple linespacing. Fig. 3 is a view showing the mechanism set for single line-spacing.

Type bars 1 strike on the front of a laten, "2, winch is mounted by means of anax e 3 in the ends 4 of a, platen frame. The axle carries a double ratchet or line-spacing wheel 5 having equally spaced teeth, and the teeth 6 of one portion .6? of said'wheel are opposed Y to the teeth 7 of the portion 7 of said wheel.

A slide or pawl-actuator 8 is mounted upon the platen frame end 4, and movable backwardly by a linger-lever 9. Pivoted to said actuator 8 is a pawl device 10 having two teeth 11, 12, normally out of engagement with the line-space wheel.

Whenever a backward movement is imparted to the actuator 8 by the lever 9, the tooth 11 is carried into engagement with the tooth 6 of the wheel.5 by a spring 13 at the the line-space stroke, -to rotate the platen. At the completion ol'the stroke, 275 a nose 14 of the pawl device lllengages an e'l-b'utment or stop 15, fixed upon the platen frame; and at the same instant the tooth 12' engages a tooth 7 of the other portion 7 01' the line-space wheel, to check or look the so same, or to counteract any tendency of the platen to overthrow. It will be understood. that the tooth of the wheel portion '7 can only force t 1e nose 14 against the'stop 15, so that theplaten is locked against further ros5 tation.

The actuator S is returned forwardly. to

normal position by the usual spring 16. The

teeth] 1, 12 are withdrawn from the wheel 5 by reason of the nose 14 riding over'a trip 17 so formed upon a regulating plate 18, which is slotted'at its rear end to engage a shoulderserew 19 on the platen-frame end 4; said plate 18 being adjustable baekwardly and forwardly by a linger-lever 20, to regulate the line-spacing of the platen.

The usual detent '2] is pivoted at 22 upon the platen frame end 4, having a roll 21* which is normally pressed by spring 23 against the teeth of ther'wheel 5 to hold the. platen steady Having thus described claim:-

1. In atypewriting machine, the combination ofa revoluble platen, a pair of super.- J05 posed ratchet wheels mounted thereon, and

my invention, 1

' pawl a lever-operated slide having a pawl engaging with one wheel to rotate the platen, and on aging with the other wheel to check or 100 the platen against overthrow.

2. In a typewriting machine, the combination with a revoluble platen, of a line-space wheel therefor, a supplemental wheel mounted at the side of the line-space wheel, and a having a tooth to engage the line-space wheel to rotate the platen, and also having a tooth to enga e with the supplemental wheel to check the p aten against overthrow.

3. In a typewriting machine, the com'hie nation with a revoluble platen, of aline-space wheel therefor, a lever-operated slide having a awl provided with a tooth to en age said w eel to rotate the laten, a supp emental wheel contiguous to t 1e line-space wheel and engaged by another tooth of the pawl at the termination of a line-space stroke of the lever to lock the platen againstoverthrow.

l. In a typewriting machine, the co1nl ination with a revoluhle platen, of a toothed line space wheel normally engaged by a yielding detent, a supplemental toothed wheel at the side of and connected to the line-space wheel, and a lever-operated slide carrying a double pawl having a tooth to engage the line-space wheel to rotate the platen, and also having a tooth which at the termination of the line-space stroke of the lever enga es with the supplemental wheel to lock the p aten against overthrow.

5'. In a typewriting machine, the combination with a revoluble platen, of a ratchet wheel therefor, a lever-operated slide having a pawl engaging with the ratchet wheel to rotate the platen, a stop to limit the movement of said'pawl, a second ratchet wheel, the teeth of which are opposed to the teeth of the first ratchet wheel; said pawl also engaging the second ratchet wheel and coacting with said stop at the termination of the linespace stroke of the slide, to lock the platen against overthrow.

6. In a typewritin machine, the combination with a platen aving a ratchet wheel engaged by a yielding detent, a lever-operated actuator having a pawl normally out of engagement with the wheel and engaging therewith to rotate the platen, and a stop for limiting the movement of said pawl, ol means to prevent overthrow of'the platen, comprising a supplemental ratchet wheel, the teeth of which are opposed to the teeth of the first wheel, and the awl engaging said wheel and co-actin with the stop at the termination of the Ii actuator.

7. In a typewriting machine, the combination with a platen frame and a platen mounted on an axle in said frame, of a pair of ratchet wheels on said axle, the teeth of one ne-space stroke of the wheel opposed to the teeth of the other, a

double pawl, and a stop said pawl engagin Y one of said wheels to rotate the platen, am engaging with the other wheel and co-ac-ting with the stop, to lock the platen against overthrow.

8. In a typewriting machine, the combination with a revoluble platen, of a pair of ratchet wheels therefor, a manually-operated actuator, a device ivoted to said actuator and having a doub e-toothed pallet normally out of engagement with the wheels, and a stop engageable by said pivoted device to limit the movement of the actuator; means being provided to cause said pallet to engage one of said'wheels to rotate the platen, and to engage the other wheel at the end of the line-space stroke to lock the platen against overthrow.

JOHN C. MOLAUGHLIN.

Witnesses K. FRANKFORT, JOHN OQ SEIFERT 

